Upper row lock linkage

ABSTRACT

THE UPPER ROWS PARTICULARLY OF POST-SUPPORTED TELESCOPING PLATFORMS, SUCH AS BLEACHERS AND THE LIKE, ARE AUTOMATICALLY LOCKED AND BRACED BY LINKAGE BETWEEN THE POSTS WHEN THE POSTS ARE OPENED TO EXPANDED POSITION AND AUTOMATICALLY UNLOCKED AS THE PLATFORMS ARE MOVED ONE BY ONE TO CLOSED POSITION.

Sept. 28, 1971 R. T. SCAGGS UPPER ROW LOCK LINKAGE 3 Sheets-Sheet 1Filed June 12. 1970 FIG. 3 INVBNTOR Robert 12 Scoqqs ,Jillbnp 7444mm 7ATTORNEYS FIG. 4

Sept. 28, 1971 R. T. SCAGGS 3,608,251

UPPER ROW LOCK LINKAGE Filed June 12, 1970 3 Sheets-Sheot 2 v INVENTORober? T. Scuggs I m m w) BY au/flmwxy l'onzzalam m f), and;

/ ATTORNEYS p 1971 R. T. SCAGGS UPPER ROW LOCK LINKAGE 3 Sheets-Sheet 5Filed June 12, 1970 INVENTOR Roma? T. Scaggs ZBPW ATTORNEYS UnitedStates; Patent ifice 3,608,251 Patented Sept. 28, 1971 3,608,251 UPPERROW LOCK LINKAGE Robert T. Scaggs, Urbana, Ill., assignor to AmericanSeating Company, Grand Rapids, Mich. Filed June 12, 1970, Ser. No.45,799 Int. Cl. E04h 3/12 U.S. Cl. 52-9 6 Claims ABSTRACT OF THEDISCLOSURE The upper rows particularly of post-supported telescopingplatforms, such as bleachers and the like, are auto matically locked andbraced by linkage between the posts when the posts are opened toexpanded position and automatically unlocked as the platforms are movedone by one to closed position.

BACKGROUND AND SUMMARY In telescoping bleacher seating or othertelescoping platform structures employing traveling posts, the upperrows particularly which are carried by higher posts become less steadyand, if light construction materials are to be employed, there is aproblem in providing bracing and locking means without interfering withthe easy and accurate opening and closing of the rows. Also, when theposts reach closed or stored position, it is important to have suchbracing means nested between the adjacent posts.

I have discovered that it is possible to employ linkage between postswith connections which automatically lock rows in extended position soas to provide strong bracing between adjacent posts while at the sametime the linkage is automatically folded between posts as the rows aremoved inwardly one by one to closed position.

DRAWINGS In the accompanying drawings, FIG. 1 is a perspective view of ableacher section of five rows showing the third, fourth and fifth rowslocked in place; FIG. 2, a side view of one row showing the lockingdevice extended as it would be in locked position, if there were apreceding row; FIG. 3, a fragmentary rear view of the row shown in FIG.2; FIG. 4, a sectional 'view of the post, locking device, and foot ofone row, the section being taken as indicated at line 44 of FIG. 2; FIG.5, an enlarged fragmentary view of the upper portion of six rows,showing the locking device in both locked and folded positions; FIG. 6,a broken rear view of the six rows shown in FIG. 5, two locking devicesbeing shown folded and three locking devices shown in locked position;and FIG. 7, a top plan view on an enlarged scale of the locking devicein the opened and locked position between two posts.

DETAILED DESCRIPTION The invention is illustrated and described hereinin connection with bleacher sections containing several rows of seatingand each having a stand platform, but the invention may be used in anypost-supported telescoping platform structure in which there is need forbracing in intermediate or higher rows.

In the drawings, a bleacher section 10 is shown, the section containingseveral rows of seating as indicated by the letters a, b, c, d and e inFIG. 1. It will be understood that the section may contain twenty ormore rows, the need for bracing being greatest when the number of rowsis increased.

Each row consists of two end structures 11 stabilized by suitable crossbracing (not shown). Each end structure consists of a base channel 12with two or more casters or the form of a rectangular tubing, an uppercaster or roller 16, a platform supporting channel 17 holding a platform18, a seat support frame 19, a seat board 20, and if desired, a frontboard 21. There is also provided a cross beam or kick board 22 which notonly unites a row of posts to support the structure but also servesanother purpose which will be later described. The end structureincludes also a locking device 23, a post stopping bracket 24, and apost stopping pin 25.

As shown best in FIGS. 2 and 7, the locking device 23 consists of a link26 attached to the post 15h by means of a bolt 27 which threads into ajam nut 28 and to the post 15h, and a second link 29 attached to thefirst link 26 by means of a rivet 30 with aspacer washer 31 between thetwo links. The far end of the second link 29 has a protruding finger orcam 32 which the kick board or beam 22 strikes when the preceding row isbeing folded and causes the linkage to fold up, as shown in dotted linesin FIG. 5. The second link 29 is attached to the post 15g of thepreceding row by means of a bolt 33 which threads into a jam nut 34 andto the post 15g. The second link 29 is longer than the first link 26 andhas a stop plate 35 welded to its top side which stops the swingingaction of the linkage and locks it in the extended position.

As shown best in FIGS. 5 and 6, row M is folded into row N, with thelinkage 23n folded up between the preceding post 15m and post 1511 asshown in FIG. 6. In like manner, in row 0 linkage 230 is folded upbetween post and post 1511.

Referring to FIG. 5, row N is folded nearly all of the way into row 0,and its kick board 2211 is striking finger 32p about to unlock thelinkage 23p so that row 0 can fold into row P. Likewise, when the kickboard 220 strikes the finger 32q, the linkage 23: will unlock and foldallowing row P to fold into row Q.

As shown best in FIG. 6, the locking device 23p is shown opened andlocked between post 150 and post 15;). The succeeding locking devices23q and 23r are opened and locked.

Referring to FIG. 5, when the row is extended ready for use, as is rowP, then the post stopping bracket 240 of the preceding row 0 strikes thepost stopping pin 25p. This occurs on every row when the bleachersection is open.

In the foregoing operation, the cross beam or kick board 22 not onlyunites and supports a row of posts in a unitary structure but alsoserves as a release means for engaging the cam finger 32 of link 29 tounlock the linkage in the following row. The rollers or casters at thetop of each post and at the bottom of each post facilitate the movementof the platforms outwardly and the momentum is effective in pulling thelinks to the locking position automatically as the various sections arebeing opened. Further, in the folding of the mechanism, the linkage isconcealed and housed between the posts, as shown best in FIG. 6.

While in the foregoing specification I have set forth a specific examplein considerable detail for the purpose of illustrating the invention, itwill be understood that such details may be varied Widely by thoseskilled in the art without departing from the spirit of my invention.

What is claimed is:

1. In a telescoping structure having transversely-aligned posts andseating rows supported thereon, said posts being in stepped rows andspaced inwardly of each other to permit folding of the posts inside-by-side stored position, links pivotally connected to adjacentposts and to each other bracing said posts, at least one of said linksextending past said pivotal connection between links and having a stopplate bearing against the top of the other link, the foremost of saidlinks having a cam finger, and a cross member connected totransversely-aligned posts and engageable with said finger for liftingsaid stop plate and pivotal connection to free said links for thefolding of the adjacent posts toward each other.

2. The structure of claim 1 in which said cross member is a beamconnecting transversely-aligned posts.

3. The structure of claim 1 in which the transverselyaligned posts areequipped with said links and said beam engages and releasessimultaneously the links between the following aligned adjacent posts.

4. In a telescoping structure in which rows of posts of successivelygreater height from front to rear have forwardly-extending armsupporting seats and in which said arms in one row rest at their forwardportions on posts in the row ahead when the structure is expanded, saidposts being foldable in spaced relation with the higher posts outermost,the improvement which comprises pivotally-connected links having theirouter ends pivoted on adjacent posts and bridging the space between saidposts and locking said posts in spaced-apart relation when the posts arein expanded position, stop plate means on one of said links engageablewith the other of said links to restrain said links from swingingsubstantially below horizontal position when the posts are in expandedposition, the foremost of said links having a cam finger, and a camrelease member extending between and uniting the row of posts andengageable with said cam for moving the pivotal connection between saidlinks upwardly to permit folding of said posts toward each other.

5. The structure of claim 4 in which the foremost of said links islonger than the other link and has an end portion extending beyond thelink pivot.

6. The structure of claim 4 in which said posts are provided at theirtops with rollers on which flanges of superposed platforms travel in theclosing of the linkage.

References Cited UNITED STATES PATENTS 3,142,871 8/1964 Harms 52-10 JOHNE. MURTAGH, Primary Examiner

